Impact of social stress in early ontogenesis on food addiction and ghrelin levels in the hypothalamus of rats

BACKGROUND: Factors that can trigger episodes of binge (compulsive) eating include psychological and physical stress. Our studies have shown that maternal deprivation in early ontogenesis leads to an increase in elements of gambling addiction in the Iowa Gambling Task test. This raises the question of the role of maternal deprivation in the development of other types of non-chemical addictions, particularly food addiction. AIM: To study the role of ghrelin in the manifestation of food addiction elements in rats subjected to maternal deprivation in early ontogenesis. MATERIALS AND METHODS: Wistar rats were separated from their mothers for 180 minutes daily from day 2 to day 12 after birth. Male rats aged 90–100 days were used in the experiments. To induce compulsive overeating, the animals were given a high-carbohydrate diet (a mixture based on chocolate paste) for 1 hour every third day for 1.5 months. Fifteen minutes before feeding, the chocolate paste was placed within 5 cm of the rat’s reach with visual contact. After compulsive overeating was established, the number and area of ghrelin-producing neuroendocrine cells in the hypothalamus were analyzed using immunohistochemistry in intact rats and animals subjected to maternal deprivation stress. RESULTS: It was shown that intermittent consumption of the chocolate mixture predicted overeating in rats, independent of weight gain or obesity, as a result of compulsive overeating. In studying the effect of maternal deprivation on chocolate consumption, it was found that the average daily consumption in the maternal deprivation group increased (p 0.001) compared to the control group. However, there was no significant difference in standard food consumption between the maternal deprivation and control groups. The number and area of ghrelin-producing neuroendocrine cells in the lateral portion of the medial arcuate nucleus of the hypothalamus were reduced in rats after maternal deprivation. CONCLUSIONS: It was concluded that early psychogenic stress from maternal deprivation causes a dysregulation of the ghrelin system, contributing to elements of food addiction in rats.